1. Field of the Invention
This invention relates to a white balance adjusting device for automatically adjusting the white balance on the basis of the output signal from the image sensing element or the output signal from an external sensor.
2. Description of the Related Art
The technique of automatically adjusting the white balance on the basis of the output signal from the image sensing element or the external sensor is known. For example, the former method is to control the mu-factors of the R and B signals so that the integrated value of the color difference signal approaches the predetermined reference value.
In the case of adopting such a white balance adjusting method, a drawback is encountered in that when a colored object is very near, or an object lies in front of a colored wall such that a particular color occupies a large proportion of the area of the image frame, the white balance adjustment is caused to err so that the object image is in unnatural colors. Particularly the shift of color correction to green or cyan is very unpleasant to the human eye. In the art of automatic white balance adjustment, therefore, to remove such a drawback is regarded as a very important problem.